document transceiver specs

diff --git a/src/Radio/radio.cxx b/src/Radio/radio.cxx
index e1b7ad9fee32aac377c508a267a13dfd1d66dd2b..fb73dffedf6ee16a7997ea70908d02f03b85f553 100644 (file)
--- a/src/Radio/radio.cxx
+++ b/src/Radio/radio.cxx
@@ -40,9 +40,15 @@ FGRadio::FGRadio() {
        
        /** AM transmitter power in dBm.
        *       Note this value is calculated from the typical final transistor stage output
-       *       small aircraft have portable transmitters which operate at 36 dBm output (4 Watts)
+       *       small aircraft have portable transmitters which operate at 36 dBm output (4 Watts) others operate in the range 10-20 W
        *       later possibly store this value in aircraft description
        *       ATC comms usually operate high power equipment, thus making the link asymetrical; this is taken care of in propagation routines
+       *       Typical output powers for ATC ground equipment, VHF-UHF:
+       *       40 dBm - 10 W (ground, clearance)
+       *       44 dBm - 20 W (tower)
+       *       47 dBm - 50 W (center, sectors)
+       *       50 dBm - 100 W (center, sectors)
+       *       53 dBm - 200 W (sectors, on directional arrays)
        **/
        _transmitter_power = 43.0;
        
@@ -85,7 +91,9 @@ void FGRadio::receiveChat(SGGeod tx_pos, double freq, string text, int ground_to
 ***/
 double FGRadio::receiveNav(SGGeod tx_pos, double freq, int transmission_type) {
        
-       // need to implement transmitter power
+       // typical VOR/LOC transmitter power appears to be 200 Watt ~ 53 dBm
+       // vor/loc typical sensitivity between -107 and -101 dBm
+       // glideslope sensitivity between -85 and -81 dBm
        if ( _propagation_model == 1) {
                return LOS_calculate_attenuation(tx_pos, freq, 1);
        }